Principles of diffusion-weighted imaging -- Normal brain and artifacts -- Brain edema: Classification. Cytotoxic edema. Edema of neuron and glial cell. Intramyelinic edema. Axonal edema. Vasogenic edema -- Infarction: Arterial infarction. Venous infarction -- Dementia: Alzheimer's. Multi-infarct dementia. Other dementias. HIV dementia -- Hemorrhage -- Vasculitis/Vasculopathy: Behcet. Systemic lupus erythematosus. Posterior reversal encephalopathy syndrome. Drug induced -- Epilepsy: Postictal encephalopathy. Status epilepticus -- Demyelinating and degenerative diseases: ADEM. Multiple sclerosis. Creutzfeldt-Jakob disease -- Toxic and metabolic diseases: Drug-induced encephalopathy. Mitochondrial encephalopathy. Phenylketonuria. Osmotic myelinolysis. Marchiafava-Bignami disease -- Infectious diseases: Brain abscess. Extra-axial abscess. Encephalitis. Septic emboli -- Trauma: Diffuse axonal injury. Brain contusion -- Brain neoplasm: Epidermoid. Meningioma. Lymphoma. GBM. Metastasis. PNET -- Pediatrics.Diffusion-weighted MR imaging is widely accepted as a means to identify stroke, thus enabling rapid and effective treatment. Over the past four years, these expert authors have presented over 30 exhibits and scientific reports on diffusion-weighted imaging at the RSNA and the American Society of Neuroradiology (ASNR), and more than 10 of these presentations have been recognized by specific awards. Diffusion-Weighted MR Imaging of the Brain’s chapters range from basic principles to interpretation of diffusion-weighted MR imaging and specific disease. This is a valuable reference for radiologists, neurologists, neurosurgeons as well as residents, fellows, radiology technologists.